servirse

infinitive of servir combined with se

(intransitive, transitive) to serve (to be a servant or worker; to render service)
(intransitive, transitive) to serve (to be a servant for; to work for)
(intransitive) to be of use, to be good for
(intransitive) to serve (to usefully take the place of something else)
(intransitive) to serve (to be in military service)
(intransitive, transitive) to serve (to set down (food or drink) on the table to be eaten)
(intransitive) to serve (to lead off with the first delivery over the net in tennis, volleyball, ping pong, badminton, etc.)
(reflexive) to help oneself to (to take freely)